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arXiv · 1905.08970

Critical exponents in mean-field classical spin systems

Yoshiyuki Y. Yamaguchi·Debraj Das·Shamik Gupta
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Abstract

For a mean-field classical spin system exhibiting a second-order phase transition in the stationary state, we obtain within the corresponding phase space evolution according to the Vlasov equation the values of the critical exponents describing power-law behavior of response to a small external field. The exponent values so obtained significantly differ from the ones obtained on the basis of an analysis of the static phase-space distribution, with no reference to dynamics. This work serves as an illustration that cautions against relying on a static approach, with no reference to the dynamical evolution, to extract critical exponent values for mean-field systems.

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Yoshiyuki Y. Yamaguchi, Debraj Das, Shamik Gupta. 2019-05-22. Critical exponents in mean-field classical spin systems. https://doi.org/10.1103/physreve.100.032131

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